Non-toxigenic Corynebacterium diphtheriae endocarditis: A cluster of five cases.

Background: Classical toxin-mediated respiratory diphtheria has become less common because of widespread effective vaccination globally but invasive disease as a result of non-toxigenic strains of Corynebacterium diphtheriae is not prevented by vaccination and may result in severe disease, including infective endocarditis (IE). Objectives: To describe the outbreak and subsequent investigation of a cluster of five cases of non-toxigenic C. diphtheriae endocarditis. Method: A retrospective observational case series of five cases of non-toxigenic C. diphtheriae endocarditis identified in the rural West Coast district of the Western Cape province of South Africa between May 2021 and June 2021. Results: Non-toxigenic C. diphtheriae IE had an aggressive clinical course with high mortality in this cohort. Only one of five patients survived to hospital discharge. The surviving patient received a prompt diagnosis with early surgical intervention but still had a complicated clinical course. Notably, only one case had a pre-existing risk factor for IE, namely a prosthetic valve. Whole genome sequencing of clinical isolates confirmed that all isolates were of the same novel sequence type of non-toxigenic C. diphtheriae but despite a thorough investigation no epidemiological link was ever found between the cases. Conclusion: Non-toxigenic strains of C. diphtheriae are less well known but may be highly virulent and cause severe invasive disease. Contribution: This is the largest cluster of non-toxigenic C. diphtheriae IE ever described in South Africa and expands the body of literature on this unusual but possibly emerging infection.

Early surgery determines prognosis in patients with infective endocarditis: outcome in patients managed by an Endocarditis Team-a prospective cohort study.

Background: Infective endocarditis (IE) in South Africa is associated with significant morbidity and mortality, despite occurring in younger patients with fewer co-morbidities. Possible contributors include the high rates of blood culture negative endocarditis, high rates of mechanical valve replacement and the lack of inter-disciplinary coordination during management. Methods: The Tygerberg Endocarditis Cohort (TEC) study prospectively enrolled patients with IE between November 2019 and April 2021. All patients were managed by an Endocarditis Team with a set protocol for organism detection and a strategy of early surgery limiting the use of prosthetic material. Results: Seventy-two consecutive patients with IE were included, with a causative organism identified in 86.1% of patients. The majority of patients had a guideline indication for surgery (n=58; 80.6%). The in-hospital mortality rate was 18%, with a 6-month mortality rate of 25.7%. Surgery was performed in 42 patients (58.3%), with prosthetic valve (PVE) replacement in 32 (76.2%), conventional repair surgery in 8 (19.1%) and mitral valve reconstruction in 2 (4.8%) of patients. Patients who underwent surgery had a significantly lower in-hospital (4.8% vs. 56.3%; P<0.01) and 6-month (4.9% vs. 75.0%; P<0.01) mortality rate as compared with patients with an indication for surgery who did not undergo surgery. Conclusions: We have observed a reduction in the 6-month mortality rate in patients with IE following the establishment of an Endocarditis Team, adhering to a set protocol for organism detection and favouring early repair or reconstruction surgery. Patients who underwent surgery had a significantly lower mortality rate than patients with an indication for surgery who did not undergo surgery. Preventable residual mortality was driven by surgical delay.

Tuberculous bronchial stenosis: Diagnosis and role of interventional bronchoscopy.

The reported prevalence of tuberculous bronchial stenosis in children is unknown and rarely reported in English-speaking literature. In adult patients with pulmonary tuberculosis, it varies from 40% in an autopsied series in the preantibiotic era to 10% in patients who have undergone routine bronchofibroscopy in modern times. We describe our experience of four cases of confirmed bronchial stenosis due to MTB collected between January 2000 and June 2021 in this case series descriptive study. The diagnosis of bronchial stenosis due to TB was made on flexible bronchoscopy. A TB diagnosis was made if MTB was cultured from respiratory secretions, when Ziehl-Neelsen smear or GeneXpert MTB/RIF test was positive, or if a chest radiograph revealed radiographic features typical of MTB. Bronchial stenosis due to TB is rare even if airway compression is frequently seen. Although an early diagnosis of bronchial stenosis due to TB is difficult on chest X-rays, all children in this series demonstrated parenchymal changes distal to the stenosis ranging from hyperinflation and lobar collaps to bronchiectasis. If bronchial stenosis resulting from TB disease is diagnosed early, balloon dilatation as described in this report, may be an effective and safe intervention, preventing long-term complications such as irreversible lung destruction, that may require pneumonectomy.

Pulmonary Echinococcus in children: A descriptive study in a LMIC.

BACKGROUND: Echinococcus granulosus is a major public health problem in lower middle-income countries (LMIC). Children are commonly diagnosed with cysts in the lungs and/or the liver. OBJECTIVES: The purpose of this study was to describe a pediatric cohort diagnosed with pulmonary Cystic Echinococcus (CE) and treated with a combination of medical and surgical therapy. METHODS: This was a retrospective study performed between July 2017 and December 2020 at Tygerberg Hospital, South Africa. Clinical, laboratory, radiological, medical, and surgery-related outcomes were reviewed. RESULTS: The cohort consisted of 35 children, 17 (49%) were male, with a mean age of 9 ± 5.4 years. The most frequently encountered presenting symptom was cough (93%) followed by fever (70%). Isolated pulmonary CE accounted for the majority of cases (74%) with left lower lobe predominance. A significant proportion of the cohort exhibited chest computed tomography (CT) characteristics consistent with complicated pulmonary CE. Eighteen (58%) children had a positive indirect hemagglutination assay (IHA) test result. All children received medical treatment whilst 30 (86%) of children required surgery. Children with complicated pulmonary CE stayed a mean of 12.5 ± 6.6 days, while those with simple cysts stayed 6.8 ± 1.5 days. CONCLUSION: Isolated pulmonary CE is common in children, whereas extrapulmonary cysts are uncommon. Pulmonary CE is diagnosed using chest X-ray and, CT imaging. IHA serology has limited diagnostic utility for pulmonary CE. Combined surgery and chemotherapy remains the gold standard for treating pulmonary CE.

Diagnostic utility of bronchoalveolar lavage in children with complicated intrathoracic tuberculosis.

INTRODUCTION: Bronchoscopy can be a useful tool in children with pulmonary tuberculosis (PTB) with severe disease potentially requiring intervention or in the face of diagnostic dilemmas. The aim of this study was to determine the value of Xpert MTB/RIF assay (Xpert) on bronchoalveolar lavage (BAL) samples in children with complicated PTB. METHODS: Retrospective analysis of children with clinically diagnosed PTB, who underwent routine bronchoscopy over a 5-year period at a large referral hospital. BAL and other respiratory samples were tested by microscopy, culture, and Xpert. We explored whether clinical, radiographic and bronchoscopy findings, and duration of antituberculosis treatment were associated with bacteriological confirmation. RESULTS: One hundred and twelve out of one hundred and forty-six (76.7%) children (median age 16 months) were on antituberculosis treatment for a median of 10 days at the time of bronchoscopy. Overall, bacteriological confirmation was achieved in 115 (78.7%), with 101 (69.2%) detected on BAL. Of those bacteriologically confirmed on BAL, 61.4% were positive by both Xpert and culture, 34.7% only by Xpert, and 3.9% only by culture. Sensitivity and specificity of Xpert compared with culture on BAL samples for children not on antituberculosis treatment were 94.1% (95% confidence interval [CI]: 71.3, 99.8) and 68.7% (95% CI: 41.3, 89.0), respectively. CONCLUSIONS: In children undergoing bronchoscopy for complicated PTB, Xpert testing of BAL had a high diagnostic yield in children already on antituberculosis treatment. Bronchoscopy should be considered if noninvasive respiratory specimens fail to confirm complicated TB.

Hydatid Disease With Pseudoaneurysm Formation of the Descending Thoracic Aorta.

Human Echinococcus disease is a zoonosis that primarily affects the liver and lungs. We report a rare case of hydatid disease in the posterior mediastinum with pseudoaneurysm formation of the descending thoracic aorta and erosion of thoracic vertebral bodies. The patient was surgically treated with removal of multiple daughter cysts and primary repair of the aorta.

Management of children with tuberculous broncho-esophageal fistulae.

INTRODUCTION: Broncho-esophageal fistula (BOF) is a rare complication of Mycobacterium tuberculosis (MTB). TB-associated BOF presents either as acute respiratory failure, aspiration pneumonia or as a complication of surgical decompression of thoracic lymph nodes. METHODS: All children with TB- associated BOF were included. TB was diagnosed if MTB was cultured from respiratory secretions, Ziehl-Neelsen (ZN) smear was positive, GeneXpert MTB/RIF was positive or a chest radiograph revealed radiographic features typical of TB. BOF was diagnosed by a contrast swallow study and/or flexible bronchoscopy. Chest computed tomography (CT) scan was performed, if required. RESULTS: Total of 20 children were diagnosed with TB-associated BOF between 1999 and 2019, with a 75% survival. A total of 85% BOF involved the left main bronchus. A total of 80% of patients were MTB culture or ZN smear-positive. Chest X-ray abnormalities included: extensive parenchymal disease (80%) and lymph gland enlargement (45%). CT features included visualization of the BOF (60%), esophageal air (73%) and pneumomediastinum (40%). BOF closure was achieved by surgical closure (46%), spontaneous closure (26%), fibrin glue (13%), and esophageal stent (13%). Multivariant regression analysis showed that C- reactive protein (CRP), albumin and CRP/albumin ratio were associated with mortality. CONCLUSION: Most TB-associated BOF are left-sided. It presents either acutely, with respiratory failure, or with chronic respiratory symptoms of aspiration. Children requiring invasive ventilation have high mortality. Most TB-associated BOF requires surgical intervention, although the use of fibrin glue offers an attractive alternative option.

A case report of an aorto-pulmonary-venacaval fistula after penetrating cardiac injury.

BACKGROUND: Penetrating cardiac injury (PCI) is an accepted burden in high violent crime areas. Traumatic intracardiac fistulae are however not that commonly detected on initial presentation, with most of these injuries being detected post-operatively or at routine follow-up. The literature is devoid of general principles around the pre-operative planning and intra-operative management in these cases, and thus warrant documented case reports by clinical units experienced in the management of these challenging clinical scenarios. CASE SUMMARY: We describe a case report of a 29-year-old male patient presenting to our Cardiothoracic Unit with an aorto-pulmonary-venacaval fistula after a traumatic PCI. We describe the clinical presentation, diagnostic challenges, and institutional experience in the operative management of this case. DISCUSSION: The patient was treated successfully with repair via sternotomy and femoral cardiopulmonary bypass with no neurological, pulmonary, or cardiac sequelae at early follow-up. The importance of selective pre-operative imaging in PCI, appropriate pre-operative surgical planning, and surgical experience in the management of these injuries is highlighted in this case presentation.

Reinventing the Saphenous Vein: Reconstructing the Anterior Mitral Leaflet With a Saphenous Vein.

Mitral valve repair can sometimes require leaflet augmentation or a patch repair of a defect in the leaflet. No ideal patch material is currently available that can grow and adapt to the mitral leaflet. This report describes a new technique using autologous saphenous vein as patch material. The saphenous vein is untreated, living tissue and remains flexible as a patch or leaflet augmentation for up to 3 years on echocardiography.

Replacing the Anterior Mitral Valve Leaflet With Autologous Jugular Vein in a Sheep Model.

BACKGROUND: This study evaluated the use of an autologous vein graft, supported by expanded polytetrafluoroethylene (ePTFE) chordae tendineae, to replace an anterior mitral valve leaflet. METHODS: A double-layered autologous jugular vein graft, supported by ePTFE chords, was used to create an anterior mitral valve leaflet in 21 sheep. Mitral valve function was monitored with echocardiography for up to 10 months. Surviving sheep were euthanized between 6 and 10 months later, and vein implants were examined histologically. RESULTS: One sheep died intraoperatively. Fourteen sheep had trace to mild mitral regurgitation (MR), 5 had mild to moderate MR, and 1 had moderate to severe MR. Ten sheep died between 2 days and 6.2 months. Echocardiography at 6 months showed MR progression in 8 of 11 sheep. The vein leaflet developed intimal fibroplasia and fibrous proliferation in response to the increased stress on the tissue, but the vein remained flexible without shortening or contracture. The 6- to 10-month vein implants showed viability with intact endothelium, myofibroblasts, collagen, and elastin. A normal healing pattern was seen at the suture lines, and no calcification was observed in the vein leaflet apart from the ePTFE sutures. CONCLUSIONS: Autologous vein has the potential to function as a mitral valve leaflet substitute because it adapted morphologically and remained viable in the intracardiac position. Technical refinement in creating and implanting the leaflet is needed to improve the progression of MR.

Decompression of enlarged mediastinal lymph nodes due to mycobacterium tuberculosis causing severe airway obstruction in children.

BACKGROUND: Large airway compression by enlarged tuberculosis (TB) lymph nodes results in life-threatening airway obstruction in a small proportion of children. The indications, safety, and efficacy of TB lymph node decompression are inadequately described. This study aims to describe the indications and efficacy of TB lymph node decompression in children with severe airway compression and investigate variables influencing outcome. METHODS: A prospective cohort of children (aged 3 months to 13 years) with life-threatening airway obstruction resulting from TB lymph node compression of the large airways were enrolled. The site and degree of airway obstruction were assessed by bronchoscopy and chest computed tomography scan. RESULTS: Of the 250 children enrolled, 34% (n = 86) required transthoracic lymph node decompression, 29% as an urgent procedure and 71% (n = 63) after failing 1 month of antituberculosis treatment that included glucosteroids. Compression (less than 75%) of the bronchus intermedius (odds ratio 2.28, 95% confidence interval: 1.29 to 4.02) and left main bronchus (odds ratio 3.34, 95% confidence interval: 1.73 to 6.83) were the best predictors for lymph node decompression. Human immunodeficiency virus status, drug resistance, and malnutrition were not associated with decompression. Few complications (self-limiting, 8%) or treatment failures (2%) resulted from the decompression. There were no deaths. CONCLUSIONS: In one third of children with TB, severe airway obstruction caused by enlarged lymph nodes requires decompression. Transthoracic decompression can be safely performed with low complication, failure, and fatality rates.

A new technique for repair of a dislocated sternoclavicular joint using a sternal tension cable system.

An unstable anterior or posterior sternoclavicular joint dislocation can cause severe morbidity with poor shoulder movement and strength. These dislocations need to be repaired, which can be challenging. Many different procedures have been described to obtain a stable joint fixation with varying results. We report a new technique for repairing a sternoclavicular joint dislocation by using a figure-of-eight sternal cable system. This procedure is relatively simple and reproducible to create a stable and functional sternoclavicular joint.

Delayed pericardial effusion following stab wounds to the chest.

INTRODUCTION: Delayed pericardial effusion following penetrating cardiac trauma has not been commonly reported, and the exact incidence remains unknown. It was more common before 1960, when pericardiocentesis was still a popular treatment for stable patients presenting with a stab wound to the heart. MATERIAL AND METHODS: During an 8-year period, 24 patients were diagnosed with delayed pericardial effusions following a recent stab wound over the chest. Nine patients had been initially treated at our trauma unit, and the remaining 15 patients were referred by a peripheral clinic. RESULTS: Diagnosis was confirmed by cardiac ultrasound or echocardiogram. Sixteen patients were adequately treated by subxiphoid drainage. Sternotomy was performed in five patients, left thoracotomy in two and right thoracotomy in one patient. No actively bleeding injuries were found. Three patients had active infection in the pericardial space. Fever, pleural effusions and ascites were common associated findings. Additional procedures performed included laparotomy for acute abdominal pain in two patients (both negative), and simultaneous drainage of a pleural empyema. Two patients with staphylococcal pericardial infections required subsequent pericardiectomy. SUMMARY: The diagnosis of a penetrating cardiac patient may be missed in a stable patient, and patients may present with delayed pericardial effusions and tamponade. Post pericardiotomy syndrome may be the most common cause of delayed pericardial effusion, followed by sepsis. Subxiphoid pericardial window is an adequate form of treatment. Recent literature reveals that occult cardiac injury is not uncommon, thus a case should be made to actively investigate all patients with precordial stab wounds with cardiac ultrasound or echocardiogram.

Pericardial rupture and cardiac herniation after blunt chest trauma.

Pericardial rupture after blunt chest trauma is rare and is associated with a high mortality rate. We describe a patient with traumatic pericardial rupture and cardiac herniation who was successfully treated surgically. Traumatic pericardial rupture is difficult to diagnose preoperatively but should be suspected whenever there is severe blunt chest trauma. If pericardial rupture is not recognized and treated promptly it could be fatal owing to cardiac herniation.